Arguments 
=========

Crowbook can take a number of arguments, generally in the form:

```bash
crowbook [OPTIONS] [BOOK]
```

The most important argument is obviously the book
configuration file. It is mandatory in most cases: if you don't 
pass it, Crowbook will simply display an error. In a normal use case this is
the only argument you'll need to pass, as most options will be set in this configuration file. 

It is, however, possible to pass more arguments to `crowbook`:

`--create`
---------

**Usage**: `crowbook [BOOK] --create file_1.md file_2.md ...`

(or `crowbook [BOOK] -c file_1.md file_2.md ...`)

Creates a new book from a list of Markdown files. It will generate a
book configuration file with all file names specified as
chapters. It either prints the result to stdout (if `BOOK` is not
specified) or generate the file `BOOK` (or abort if it already
exists). 

```bash
crowbook foo.book --create  chapter_1.md chapter_2.md chapter_3.md
```

will thus generate a file `foo.book` containing:

```yaml
author: Your name
title: Your title
lang: en

## Output formats

# Uncomment and fill to generate files
# output.html: some_file.html
# output.epub: some_file.epub
# output.pdf: some_file.pdf

# Or uncomment the following to generate PDF, HTML and EPUB files based on this file's name
# output: [pdf, epub, html]

# Uncomment and fill to set cover image (for EPUB)
# cover: some_cover.png

## List of chapters
+ chapter_1.md
+ chapter_2.md
+ chapter_3.md
```

while

```bash
crowbook --create chapter_1.md chapter_2.md chapter_3.md
```

will print the same result, but to stdout (without creating a file).

`--single`
----------

**Usage**: `crowbook --single <FILE>`

(or `crowbook -s <FILE>`)

This argument allows you to give `crowbook` a single Markdown file. This
file can contain an inline YAML block to set some book options. Inline
YAML blocks must start and end with a line containing only `---` (three dashes). E.g:

```yaml
---
author: Joan Doe
title: A short story
output: [html, epub, pdf]
---

Content of the story in Markdown.
```

If this YAML block is not at the beginning of a file, it must also be
preceded by a blank line.

This allows to not have to write a `.book` configuration file for a
short story or an article. `crowbook -s foo.md` is rougly equivalent to having a book
configuration file containing:

```yaml
! foo.md
```

That is, the chapter heading (if any) won't be displayed in the output
documents (though they still appear in the TOC).

> Note that by default, using `--single` or `-s` sets the default LaTeX class
> of the book to `article` instead of `book`.


`--set` 
-------

**Usage**: `crowbook <BOOK> --set [KEY] [VALUE]...`

This argument takes a list of  `KEY` `VALUE` pairs and allows setting or
overriding a book configuration option. All valid options in the
configuration files are valid as keys. For more information, see
[the configuration file](config.md).

```bash
$ crowbook foo.book --set tex.paper.size a4paper
```

will override the paper size for PDF generation. 

`--list-options`
----------------

**Usage**: `crowbook --list-options`

(or `crowbook -l`)

Displays all the valid options that can be used, whether in a book configuration
file, with `--set`, or in an inline YAML block.

`--print-template`
------------------

**Usage**: `crowbook --print-template <TEMPLATE>`

Prints the built-in template to stdout. Useful if you want to
customize the appearance of your document. E.g., if you want to modify
the CSS used for HTML rendering:

```bash
$ crowbook --print-template html.css > my_style.css
# edit my_style.css in your favourite editor
$ crowbook my.book --set html.css my_style.css
# or add "html.css: my_style.css" in my.book
```

`--stats`
------------

**Usage**: `crowbook --stats <BOOK>` 

(or `crowbook -S <BOOK>`)

Display some statistics (word and character counts) about the book.

`--proofread`
-------------

**Usage**: `crowbook --proofread <BOOK>`

(or `crowbook -p <BOOK>`)

Equivalent to `--set proofread true`. Enable proofreading. See [Proofreading](proofreading.md).

`--verbose`
-----------

**Usage**: `crowbook <BOOK> --verbose`

If this flag is set, Crowbook will print more warnings it detects while
parsing and rendering.

`--to`
------

**Usage**: `crowbook <BOOK> --to [FORMAT]`

(or `crowbook <BOOK> -t [FORMAT]`)

Generate only the specified format. `FORMAT` must be either `epub`,
`pdf`, `html`, `html.dir`, `odt` or `tex`.

If an output file for the format is not specified in the book
configuration file, `crowbook` will fail to render PDF, ODT and EPUB,
whereas it will print HTML and TeX files on stdout. It is, however, 
possible to specify a file with the `--output` option.

### Examples ###

```bash
crowbook --to html foo.book
```

will generate some HTML, and prints it either to the file specified by
`output.html` in `foo.book`, or to stdout if it is not specified.

```bash
crowbook --to pdf --output foo.pdf foo.book
```

will generate a `foo.pdf` file.

`--output`
---------

**Usage**: `crowbook <BOOK> --to <FORMAT> --output <FILE> `

(or `crowbook -t <FORMAT> -o <FILE> <BOOK>`)

Specifies an output file. Only valid when `--to` is used.


`--lang`
----------

**Usage**: `crowbook --lang <LANG>`

(or `crowbook -L <LANG>`)

Set the runtime language used by Crowbook. Currently, only a french
translation is available. By default, Crowbook uses the `LANG`
environment variable to determine which language to use, but this
option allows to override it (e.g. for operating systems that don't
use such an option, such as Windows).

### Example 

`$ crowbook --lang fr --help`

will display Crowbook's help message in french.

> Note that this argument has nothing to do with the `lang` option
> that you can set in the book configuration file, which specifies the
> language *of the book*. This argument specifies the language of the text messages
> that Crowbook will display while running, but has no effect on the generated documents.